Found 97 demos with an expect file.
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<b>Fatal error</b>:  Uncaught Error: Call to undefined function exec() in /home/innovecobranca/api/notice.innovecobrancas.com.br/vendor/reactivex/rxphp/demo/test.php:6
Stack trace:
#0 /home/innovecobranca/api/notice.innovecobrancas.com.br/vendor/reactivex/rxphp/demo/test.php(15): run_cmd('/home/innovecob...')
#1 /home/innovecobranca/api/notice.innovecobrancas.com.br/vendor/reactivex/rxphp/demo/test.php(55): run_demo('/home/innovecob...')
#2 /home/innovecobranca/api/notice.innovecobrancas.com.br/vendor/reactivex/rxphp/demo/test.php(65): main('/home/innovecob...')
#3 {main}
  thrown in <b>/home/innovecobranca/api/notice.innovecobrancas.com.br/vendor/reactivex/rxphp/demo/test.php</b> on line <b>6</b><br />